I can't say I've experienced this (being that I drive an '09), but my visual read-out flashes when I've been driving for 1 hour, and I think maybe again when it's been 2... I've only caught it doing so once, when I happened to be looking.
Anyway, perhaps that's what yours is telling you, just in a different way?
Anyway, perhaps that's what yours is telling you, just in a different way?